JP4931762B2 - Conveyor scale - Google Patents

Description

  The present invention relates to a conveyor scale that measures various materials to be conveyed such as various raw materials and products in the middle of conveyance.

  Conventionally, as this type of conveyor scale, a scale is provided in a belt conveyor that conveys the object to be conveyed, and the weight of the object to be conveyed and the speed of the belt passing over the scale are electrically detected, and these are detected. There are some which calculate based on the signal to obtain the transport amount (for example, see Patent Documents 1 and 2). According to this type of conveyor scale, it is possible to continuously measure the transport amount of the object to be transported without impairing the transport efficiency.

Japanese Patent Publication No. 1-58446 No. 1-245579

  However, in the conventional conveyor scale, since the scale attached to the belt conveyor always measures, there is a problem that the zero point correction that determines the zero point as a reference of the scale cannot be performed and the measurement accuracy is low.

  As a conveyor scale that can solve such a problem, there is a conveyor scale as shown in FIG. The conveyor scale 200 shown in FIG. 18 (a) is arranged on the upstream upper stage and the downstream lower stage of the transport path, respectively, and includes an upper belt conveyor 201 and a lower belt conveyor 202 dedicated for transport without a scale. A hopper scale 203 is provided in the middle of the conveyance path between the upper belt conveyor 201 and the lower belt conveyor 202, and has a storage / discharge function and a weighing function. In this conveyor scale 200, when the transported object H transported by the upper belt conveyor 201 is put into the hopper scale 203 to some extent, the operation of the upper belt conveyor 201 is temporarily performed as shown in FIG. Then, the weight of the transported object H accommodated in the hopper scale 203 is measured, and when the measurement is completed, the transported object H in the hopper scale 203 is moved to the lower stage as shown in FIG. When the discharge is completed on the belt conveyor 202 and the discharge is completed, as shown in FIG. 18 (a), the transported object H is input into the hopper scale 203 by the activation of the upper belt conveyor 201. ) To (c) are repeatedly performed.

  According to the conveyor scale 200, the transported object H in the hopper scale 203 is weighed every time a certain amount of the transported object H is put into the hopper scale 203, and after the discharge after the weighing is completed, Since the zero point correction can be performed before the transported object H is put in, the measurement accuracy can be remarkably improved as compared with the conventional conveyor scale that cannot perform the zero point correction.

  However, in this conveyor scale 200, when the hopper scale 203 is weighed, the object H cannot be put into the hopper scale 203, so the operation of the upper belt conveyor 201 must be stopped, and the upper belt There is a problem in that the operation of the conveyor 201 becomes discontinuous and the transportation efficiency is lowered.

  The present invention has been made to solve such a problem, and an object of the present invention is to provide a conveyor scale capable of continuously measuring with high accuracy without lowering the transport efficiency. is there.

In order to achieve the above object, the conveyor scale according to the first invention comprises:
It is a conveyor scale that weighs the object to be transported during transportation,
An upper belt conveyor disposed in the upper stage on the upstream side of the transport path;
A lower belt conveyor disposed in the lower stage on the downstream side of the conveying path;
Three or more measuring tanks placed in the middle of the conveyance path between the upper belt conveyor and the lower belt conveyor, into which the objects to be conveyed conveyed by the upper belt conveyor are put,
A support frame for supporting the three or more measuring tanks;
A to-be-conveyed material input switching damper for switching the input of the to-be-conveyed material from the upper belt conveyor to each weighing tank;
A weight measuring means for measuring the weight of the object to be conveyed put in each of the weighing tanks;
A transported object discharge gate for discharging the objects to be conveyed to the thrown into the measuring tank on the lower belt conveyor,
The weight measuring means includes at least the same number of load detectors as the number of the weighing tanks that support the support frame, a storage unit that stores the two-dimensional gravity center position information of each weighing tank, and the load detectors. A weight calculation unit configured to calculate a content weight of each weighing tank based on a load signal and center-of-gravity position information stored in the storage unit is configured. .

ただし、

The second invention is the first invention, wherein the weighing tank is composed of four weighing tanks of a first weighing tank, a second weighing tank, a third weighing tank, and a fourth weighing tank, and the load The detector is composed of four load cells, a first load cell, a second load cell, a third load cell, and a fourth load cell,
The suspension support point of the support frame by the first load cell is the origin O: (0, 0), and the gravity center positions of the four weighing tanks are arranged at arbitrary four points on the support frame,
The two-dimensional center-of-gravity position coordinates of the center of gravity of the first weighing tank are (x ₁ , y ₁ ), the two-dimensional center-of-gravity position coordinates of the center of gravity of the second weighing tank are (x ₂ , y ₂ ), and the third weighing The two-dimensional barycentric position coordinates of the center of gravity of the tank are (x ₃ , y ₃ ), the two-dimensional barycentric position coordinates of the center of gravity of the fourth weighing tank are (x ₄ , y ₄ ), and these barycentric position coordinates are measured. Register in advance in the storage unit as the two-dimensional center of gravity position information of the tank,
The distance between the support points of the suspension support point by the first load cell and the suspension support point of the fourth load cell and the distance between the support points of the suspension support point by the second load cell and the suspension support point by the third load cell Each distance is R, the distance between the support points of the suspension by the first load cell and the support point of the second load cell, and the support of the suspension by the third load cell and the fourth load cell. The distance between the support points with the point is set as S, and the distances between the support points R and S are registered in advance as basic information in the storage unit,
When the load acting on the first load cell is WA, the load acting on the second load cell is WB, the load acting on the third load cell is WC, and the load acting on the fourth load cell is WD, the contents of the measuring tank weight w _1, the content weight w ₂ of the second measuring _tank, the contents weight w ₄ of the third contents by weight of the weighing vessel w ₃ and the fourth measuring tank 94, and as determined by the following formula It is characterized by this.

However,

  In the present invention, it is preferable that the discharge amount of the transferred object by the transferred object discharging means can be adjusted (third invention).

In the present invention, when an object to be conveyed is charged to some extent among any of the three or more measuring tanks, the input of the object to be transferred is switched to another measuring tank by the object input switching damper . . While the object to be transported is being charged into another weighing tank, the weight of the object to be transported in the weighing tank into which the object has been charged is measured by the weight measuring means. After the measurement is completed, the transported object in the measuring tank that has been measured is discharged onto the lower belt conveyor by the transported object discharge gate . After that, when an object to be transported is charged to another weighing tank to some extent, the loading of the object to be transported is further switched to another weighing tank by the object to be transported switching damper . While the object to be transported is being put into the weighing tank, the weight of the object to be transported in the weighing tank into which the object has been charged is measured by the weight measuring means. After the measurement is completed, the transported object in the measuring tank that has been measured is discharged onto the lower belt conveyor by the transported object discharge gate . According to the present invention, since the feeding of the conveyed object and the weighing / discharging of the conveyed object are alternately and repeatedly performed between the plurality of weighing tanks, the upper belt conveyor can be continuously operated. At the same time, the zero point correction can be performed after the completion of the measurement / discharge and before the next object to be fed, so that highly accurate measurement can be performed continuously without lowering the transport efficiency.

Moreover, even if the number of measuring tanks increases, the weight of each of the plurality of measuring tanks can be measured with the minimum load detector, which reduces the failure rate, reduces the equipment configuration, and reduces the cost. You can go down.

  Further, by adopting the configuration of the third invention, it is possible to make the discharge amount of the conveyed object onto the lower conveyor appropriate.

  Next, specific embodiments of the conveyor scale according to the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic configuration diagram of a conveyor scale which is a premise of the present invention. 2 is an enlarged view of the main part of FIG. 1, and FIG. 3 is a view taken along the line AA of FIG.

Turkey Nbeyasukeru 1 shown in FIG. 1 is a conveyor scale for weighing the way conveying the conveying object of various raw materials and products such as roses state, the roof frame frame 2a in frame 2 (representing part only) An upper belt conveyor 3 arranged on the upstream side of the conveying path above, a lower belt conveyor 4 arranged on the downstream side of the conveying path below the ceiling frame frame 2a of the gantry 2, an upper belt conveyor 3 and a lower belt conveyor 4 A first measuring tank 5 and a second measuring tank 6 arranged in order from the left side to the right side of the figure at a position below the ceiling frame frame 2a of the gantry 2; 5 and 6, and a transported object input switching device 7 that is fixed to the ceiling frame frame 2 a of the gantry 2 through fixing means (not shown).

  Each belt conveyor 3, 4 circulates a wide endless annular belt 12; 13 between belt cars 8, 9; 10, 11 at both ends, and shows a conveyed object placed on the belt 12; 13. Is a belt conveyor having a well-known structure that conveys from the left side to the right side of the belt conveyors 3 and 4. A conveyed product input hopper 14; 15 is attached.

  As shown in FIG. 2, the first weighing tank 5 includes a first weighing hopper 16 having a square cylindrical shape opened up and down, and a first gate 17 for opening and closing a lower opening of the first weighing hopper 16. And is configured. Similarly, the second weighing tank 6 includes a square cylinder-shaped second weighing hopper 18 opened up and down, and a second gate 19 for opening and closing the lower opening of the second weighing hopper 18. ing.

  As shown in FIG. 3, the cantilever beam-shaped first load cell 21, the second load cell 22 and the third load cell 23 are arranged on the ceiling frame 2a in a predetermined arrangement so as to surround the first measuring tank 5 in a plan view. The cantilever beam shaped fourth load cell 24, fifth load cell 25 and sixth load cell 26 are fixed in a predetermined arrangement so as to surround the second measuring tank 6 in plan view.

  As shown in FIGS. 2 and 3, the first load cell 21, the second load cell 22, and the third load cell 23 are integrated with the upper end of the first weighing hopper 16 so as to protrude outward over the entire circumference. The first weighing hopper flange 27 provided is connected by a hanging rod member 28, and the first weighing tank 5 is suspended and supported by the load cells 21, 22, 23 via the hanging rod members 28, 28, 28. Has been. Similarly, the fourth load cell 24, the fifth load cell 25, the sixth load cell 26, and the second weighing hopper provided integrally with the upper end portion of the second weighing hopper 18 so as to protrude outward over the entire circumference. The flange 29 is connected to each other by a hanging rod member 28, and the second measuring tank 6 is suspended and supported by the load cells 24, 25, 26 via the hanging rod members 28, 28, 28.

  As shown in FIG. 2, a first gate opening / closing device 31 that opens and closes the first gate 17 is attached to the lower portion of the first weighing tank 5. The first gate opening / closing device 31 includes a first casing 32 that also serves as a chute that guides the object to be transported dropped from the first weighing hopper 16 to the object to be transported hopper 15 attached to the lower belt conveyor 4. Both ends of the first casing 32 are supported, and a first gate rotation shaft 33 that supports the first gate 17 so as to be rotatable between a position where the lower opening of the first weighing hopper 16 is opened and closed. It has. The first casing 32 is provided with a first gate opening / closing operation air cylinder 34 supported in the form of a trunnion, and a lever member 35 is attached to an end of the first gate rotating shaft 33. The cylinder rod tip of 34 and the tip of the lever member 35 are pin-connected. Thus, the first gate 17 is opened by the contraction of the first gate opening / closing operation air cylinder 34 to open the lower opening of the first weighing hopper 16, while the first gate opening / closing operation air cylinder 34 is extended to extend the first gate. 17 is closed and the lower opening of the first weighing hopper 16 is closed.

  A second gate opening / closing device 36 that opens and closes the second gate 19 is attached to the lower portion of the second weighing tank 6. The second gate opening / closing device 36 includes a second casing 37 that also serves as a chute that guides the object to be transported dropped from the second weighing hopper 18 to the object to be transported hopper 15 attached to the lower belt conveyor 4. Both ends are supported by the second casing 37, and a second gate pivot shaft 38 that pivotally supports the second gate 19 between a position where the lower opening of the second weighing hopper 18 is opened and closed. It has. The second casing 37 is provided with a second gate opening / closing operation air cylinder 39 supported in a trunnion type, and a lever member (similar to the lever member 35) (not shown) is provided at the end of the second gate rotating shaft 38. The cylinder rod tip of the second gate opening / closing operation air cylinder 39 and the tip of the lever member are pin-connected. Thus, the second gate 19 is opened by the contraction of the second gate opening / closing operation air cylinder 39 and the lower opening of the second measuring hopper 18 is opened, while the second gate opening / closing operation air cylinder 39 is extended to extend the second gate. 19 is closed and the lower opening of the second weighing hopper 18 is closed.

  The transferred object input switching device 7 includes a casing 41 and a switching damper 42 disposed in the casing 41. As shown in FIG. 4, the casing 41 includes a rectangular cylindrical casing main body 43 that is opened up and down, and a partition member 44 that bisects the lower opening of the casing main body 43. A receiving port 45 for receiving the object to be dropped, a first outlet 46 facing the upper opening of the first weighing hopper 16, and a second outlet 47 facing the upper opening of the second weighing hopper 18 are provided. is doing. The switching damper 42 is supported at both ends by a switching damper rotating shaft 48 supported by the casing body 43, and a first damper position (which guides the object to be conveyed taken from the receiving port 45 to the first outlet 46 ( A solid line in FIG. 4 and a second damper position (two-dot chain line in FIG. 4) for guiding the object taken in from the receiving port 45 to the second outlet 47 are rotatable. As shown in FIG. 2, a lever member 49 is attached to the end of the switching damper rotating shaft 48, and the tip of the lever member 49 is supported by the trunnion type on the ceiling frame frame 2 a of the gantry 2. The position switching operation air cylinder 50 is pin-connected to the tip of the cylinder rod. Thus, when the damper position switching operation air cylinder 50 is fully extended, the switching damper 42 is set to the first damper position, and when the damper position switching operation air cylinder 50 is fully contracted, the switching damper 42 is set to the second damper position. The switching between the first switching damper position and the second switching damper position of the switching damper 42 is performed by the expansion and contraction operation of the air cylinder 50. The casing 41 is provided with a chute 51 extending from the upper end of the casing main body 43 so as to wrap around the downstream end of the upper belt conveyor 3, and the object to be conveyed dropped from the upper belt conveyor 3 is chute 51. And is surely taken into the receiving port 45 of the casing 41.

  When the switching damper 42 is at the first damper position indicated by the solid line in FIG. 4, the object to be conveyed dropped from the downstream end of the upper belt conveyor 3 is the chute 51, the receiving port 45 of the casing 41, and the first outlet. The first weighing hopper 16 is introduced through 46. On the other hand, when the switching damper 42 is in the second damper position indicated by a two-dot chain line in FIG. 4, the object to be conveyed dropped from the downstream end of the upper belt conveyor 3 is the chute 51, the receiving port 45 of the casing 41. And the second metering hopper 18 is charged through the second outlet 47.

5 shows a schematic diagram of a control system of the conveyor scale is shown.

  In FIG. 5, the control device 60 is mainly composed of a microcomputer, and is an A / D that converts analog load signals from the load cells 21, 22, 23, 24, 25, and 26 into digital load signals. A converter 61, a weight calculator 62 that calculates the content weight of each weighing tank 5, 6 based on each load signal converted into a digital load signal by the A / D converter 61, and a weight calculator 62 A weight display signal generation unit 63 that generates a weight display signal according to the calculation result, a control program created based on the algorithm shown in the flowchart of FIG. 7, various data necessary for the calculation, calculation results, etc. A storage unit 64, a damper position switching control unit 65 for controlling the damper position switching of the switching damper 42, and a gate opening / closing operation for controlling the opening / closing operation of each gate 17, 19 And a control unit 66.

  The control device 60 is provided with a display device 67 that displays a weight value based on the weight display signal generated by the weight display signal generation unit 63. Further, between the damper position switching operation air cylinder 50 and the air supply source 68a, a damper position switching operation valve 69 made of, for example, an electromagnetic valve, which is switched by a signal from the damper position switching control unit 65, is interposed. ing. Further, between the first gate opening / closing operation air cylinder 34 and the air supply source 68b, a valve position is switched by a signal from the gate opening / closing operation control unit 66, for example, an electromagnetic valve, but the first gate opening / closing operation valve 70 is provided. It is installed. Further, between the second gate opening / closing operation air cylinder 39 and the air supply source 68c, a valve position is switched by a signal from the gate opening / closing operation control unit 66, for example, an electromagnetic valve, but a second gate opening / closing operation valve 71 is provided. It is installed.

  When the first damper position switching signal is output as a signal from the damper position switching control unit 65 to the damper position switching operation valve 69, the valve position of the damper position switching operation valve 69 extends the damper position switching operation air cylinder 50. The valve position to be made. When the damper position switching operation air cylinder 50 is fully extended, the switching damper 42 is set to the first damper position, and the object to be conveyed taken from the receiving port 45 of the casing 41 is guided to the first outlet 46. When the second damper position switching signal is output as a signal from the damper position switching control unit 65 to the damper position switching operation valve 69, the damper position switching operation valve 69 contracts the damper position switching operation air cylinder 50. The valve position to be made. When the damper position switching operation air cylinder 50 is fully contracted, the switching damper 42 is set to the second damper position, and the object to be conveyed taken from the receiving port 45 of the casing 41 is guided to the second outlet 47.

  When a first gate opening operation signal is output as a signal from the gate opening / closing operation control unit 66 to the first gate opening / closing operation valve 70, the valve position of the first gate opening / closing operation valve 70 is the first gate opening / closing operation air cylinder 34. Is a valve position for operating the contraction. When the first gate opening / closing operation air cylinder 34 is fully contracted, the first gate 17 is completely opened with respect to the lower opening of the first weighing hopper 16. When a first gate closing operation signal is output as a signal from the gate opening / closing operation control unit 66 to the first gate opening / closing operation valve 70, the valve position of the first gate opening / closing operation valve 70 is the first gate opening / closing operation air cylinder 34. It is set as the valve position which carries out expansion operation. When the first gate opening / closing operation air cylinder 34 is fully extended, the first gate 17 is completely closed with respect to the lower opening of the first weighing hopper 16.

  When the second gate opening operation signal is output as a signal from the gate opening / closing operation control unit 66 to the second gate opening / closing operation valve 71, the valve position of the second gate opening / closing operation valve 71 is set to the second gate opening / closing operation air cylinder 39. Is a valve position for operating the contraction. When the second gate opening / closing operation air cylinder 39 is fully contracted, the second gate 19 is completely opened with respect to the lower opening of the second weighing hopper 18. When a second gate closing operation signal is output as a signal from the gate opening / closing operation control unit 66 to the second gate opening / closing operation valve 71, the valve position of the second gate opening / closing operation valve 71 is set to the second gate opening / closing operation air cylinder 39. It is set as the valve position which carries out expansion operation. When the second gate opening / closing operation air cylinder 39 is fully extended, the second gate 19 is completely closed with respect to the lower opening of the second weighing hopper 18.

  The operation of the conveyor scale 1 configured as described above will be described with reference to the operation explanatory diagram of FIG. 6 and the flowchart of FIG. In the following description of the operation, both the upper belt conveyor 3 and the lower belt conveyor 4 are continuously operated at a predetermined circumferential speed. Further, the symbol “S” in FIG. 7 represents a step.

  In FIG. 6A, the switching damper 42 is set to the first damper position, the first gate 17 is closed with respect to the first weighing hopper 16, and the conveyed object H dropped from the upper belt conveyor 3 is the first weighing hopper. 16, the transported object H is stored in the first weighing tank 5. It should be noted that the transported object H is not stored in the second weighing tank 6, and the second gate 19 is closed with respect to the second weighing hopper 18.

  In the state shown in FIG. 6A, the damper position switching control unit 65 is operated in real time by the weight calculation unit 62 based on signals from the first load cell 21, the second load cell 22, and the third load cell 23. Whether the content weight of one weighing tank 5 is monitored, and whether the amount of the transported object H to the first weighing tank 5 from the content weight of the first weighing tank 5 being monitored has exceeded a certain amount Is determined (S1). When it is determined in step S <b> 1 that the amount of the object to be transported H to the first weighing tank 5 has become a certain amount or more, the damper position switching control unit 65 directs the second damper position switching signal to the damper position switching operation valve 69. And output (S2). As a result, as shown in FIG. 6B, the switching damper 42 is switched to the second damper position, and the conveyed object H dropped from the upper belt conveyor 3 is put into the second weighing hopper 18, 2 Conveyed objects H are stored in the weighing tank 6.

  Next, in the state shown in FIG. 6B, after the signals from the first load cell 21, the second load cell 22 and the third load cell 23 are stabilized, the weight calculation unit 62 performs the load cells 21, 22, 23. The content weight of the first weighing tank 5 is calculated on the basis of the signal from, and the calculation result is stored in the storage unit 64 (S3). Thereafter, the gate opening / closing operation control unit 66 outputs a first gate opening operation signal toward the first gate opening / closing operation valve 70 (S4). As a result, as shown in FIG. 6C, the first gate 17 is opened with respect to the first weighing hopper 16, and the conveyed object H is dropped from the first weighing hopper 16 and discharged onto the lower belt conveyor 4. Is done.

  Next, the gate opening / closing operation control unit 66 determines whether or not a certain time has elapsed since the first gate 17 was opened. When it is determined that the certain time has elapsed, the gate opening / closing operation control unit 66 outputs a first gate closing operation signal. Output toward the valve 70 (S5 to S6). As a result, as shown in FIG. 6D, the first gate 17 is closed with respect to the first weighing hopper 16.

  Next, in the state shown in FIG. 6 (d), the weight calculation unit 62 sets the zero that is the reference of the balance by setting the calculation value related to the content weight of the first weighing tank 5 in step S3 to zero. (S7), and then waits for the calculation of the content weight of the conveyed object H to be put into the first weighing tank 5 (S8).

  In the state shown in FIG. 6D, the damper position switching control unit 65 is a second that is calculated in real time by the weight calculation unit 62 based on signals from the fourth load cell 24, the fifth load cell 25, and the sixth load cell 26. Whether the content weight of the weighing tank 6 is monitored, and whether or not the input amount of the transported object H to the second weighing tank 6 from the monitored content weight of the second weighing tank 6 has exceeded a certain amount. Judgment is made (S9). When it is determined in step S9 that the amount of the object H to be fed into the second weighing tank 6 has reached a certain amount or more, the damper position switching control unit 65 directs the first damper position switching signal to the damper position switching operation valve 69. And output (S10). Thereby, as shown in FIG. 6E, the switching damper 42 is switched to the first damper position, and the transported object H dropped from the upper belt conveyor 3 is put into the first weighing hopper 16, The object to be transported H is stored in the 1 measuring tank 5.

  Next, in the state shown in FIG. 6 (e), after the signals from the fourth load cell 24, the fifth load cell 25, and the sixth load cell 26 are stabilized, the weight calculation unit 62 performs the load cell 24, 25, 26. The content weight of the second weighing tank 6 is calculated based on the signal from, and the calculation result is stored in the storage unit 64 (S11). Thereafter, the gate opening / closing operation control unit 66 outputs a second gate opening operation signal toward the second gate opening / closing operation valve 71 (S12). As a result, as shown in FIG. 6 (f), the second gate 19 is opened with respect to the second weighing hopper 18, and the conveyed object H is dropped from the second weighing hopper 18 and discharged onto the lower belt conveyor 4. Is done.

  Next, the gate opening / closing operation control unit 66 determines whether or not a certain time has elapsed since the second gate 19 was opened. When it is determined that the certain time has elapsed, the gate opening / closing operation signal is sent to the second gate closing operation signal. Output toward the valve 71 (S13 to S14). As a result, as shown in FIG. 6A, the second gate 19 is closed with respect to the second weighing hopper 18.

  Next, in the state shown in FIG. 6 (a), the weight calculation unit 62 sets the zero that is the reference of the balance by setting the calculation value related to the content weight of the second weighing tank 6 in step S11 to zero. (S15), and then waits for the calculation of the content weight of the object H to be loaded into the second weighing tank 6 (S16).

  Thereafter, a series of operations shown in FIGS. 6A to 6F are repeatedly performed. In the weight calculation unit 62, calculation is performed to obtain the transport amount of the transported object H by adding up the content weight values of the weighing tanks 5 and 6 sequentially stored in the storage unit 64, and the calculation result is displayed. It is displayed on the device 67.

According to the conveyor scale 1, since the weighing and discharge of on and the conveyed object H of the conveyed object H is continuously repeated alternately by the first measuring tank 5 and the second measuring tank 6, the upper belt The conveyor 3 can be operated continuously, and after the completion of weighing and discharging, zero point correction can be performed before the next object to be transported H, and it can be continuously increased without lowering the transport efficiency. Accurate weighing can be performed.

FIG. 8 is a schematic configuration diagram of a conveyor scale according to the modification of FIG . 9 is an enlarged view of the main part of FIG. 8, FIG. 10 is a view taken along the line BB of FIG. 8, showing only the main part, and FIG. 11 is an enlarged view of the main part of FIG. The figure which fractured | ruptured and represented was each shown. In this modification , the same or similar parts as those in the example shown in FIG. 1 are given the same reference numerals in the drawing, and detailed description thereof will be omitted. In the following, points different from the previous example will be mainly described. It will be explained in the following.

As shown in FIG. 11, in the conveyor scale 1A of the present modification , the first weighing hopper 16A and the second weighing are provided by providing a partition member 76 inside a rectangular tubular hopper member 75 opened up and down. The hopper 18A is integrally formed. The first weighing hopper 16A is provided with a first gate 17 for opening and closing the lower opening of the first weighing hopper 16A, whereby the first weighing tank 5A is configured, while the second weighing hopper 18A The second weighing tank 6A is configured by adding a second gate 19 for opening and closing the lower opening of the second weighing hopper 18A.

  As shown in FIG. 10, the cantilever beam-shaped first load cell 21A, second load cell 22A, and third load cell 23A are fixed to the ceiling frame frame 2a in a predetermined arrangement so as to surround the hopper member 75 in a plan view. Has been. A hopper flange 77 is integrally provided at the upper end of the hopper member 75 so as to project outward over the entire circumference. The first load cell 21A, the second load cell 22A, the third load cell 23A, and the hopper flange 77 are connected to each other by a suspension member 28, and the first weighing tank 5A and the second weighing tank 6A are both connected to the load cell 21A, 22A and 23A are supported by suspension through suspension rod members 28, 28 and 28. The hopper flange 77 serves as a support frame that supports both the first weighing tank 5A and the second weighing tank 6A.

  As shown in FIG. 9, a gate opening / closing device 80 that opens and closes the first gate 17 and the second gate 19 is attached to the lower portion of the hopper member 75. The gate opening / closing device 80 includes a casing 81 that also serves as a chute that guides the articles to be conveyed dropped from the first weighing hopper 16A and the second weighing hopper 18A to the article feeding hopper 15 attached to the lower belt conveyor 4. The first gate pivot shaft 33 is supported at both ends by the casing 81 and supports the first gate 17 so as to be pivotable between a position where the lower opening of the first weighing hopper 16A is opened and closed. Both ends are supported by the casing 81, and the second gate 19 is provided with a second gate rotation shaft 38 that supports the second gate 19 so as to be rotatable between a position where the lower opening of the second weighing hopper 18A is opened and closed. ing. The casing 81 is provided with a first gate opening / closing operation air cylinder 34 supported in a trunnion type, and a lever member 35 is attached to an end of the first gate rotating shaft 33, so that the first gate opening / closing operation air cylinder 34 The tip of the cylinder rod and the tip of the lever member 35 are pin-connected. The casing 81 is provided with a second gate opening / closing operation air cylinder 39 supported in a trunnion form, and a lever member (similar to the lever member 35) not shown is provided at the end of the second gate rotating shaft 38. The cylinder rod tip of the second gate opening / closing operation air cylinder 39 and the tip of the lever member are pin-connected. Thus, the first gate 17 is opened by the contraction of the first gate opening / closing operation air cylinder 34 and the lower opening of the first weighing hopper 16A is opened, while the first gate opening / closing operation air cylinder 34 is extended to extend the first gate. 17 is closed and the lower opening of the first weighing hopper 16A is closed. Further, the second gate 19 is opened by the contraction of the second gate opening / closing operation air cylinder 39 to open the lower opening of the second weighing hopper 18A, while the second gate opening / closing operation air cylinder 39 is extended to extend the second gate. 19 is closed and the lower opening of the second weighing hopper 18A is closed.

FIG. 12 is a schematic configuration diagram of a conveyor scale control system according to this modification .

  In the control system shown in FIG. 12, the storage unit 64 stores two-dimensional center-of-gravity position information of each of the first and second weighing tanks 5A and 6A. In the weight calculation unit 62, the load signals from the first load cell 21A, the second load cell 22A, and the third load cell 23A, and the two-dimensional gravity center position information of the weighing tanks 5A, 6A stored in the storage unit 64, Based on the above, the content weight of each of the measuring tanks 5A and 6A is calculated.

  The figure for demonstrating the measurement theory (1) of the content weight of a measuring tank is shown by FIG.

In FIG. 13, for convenience of explanation, the suspension support point by the first load cell 21A is the origin O: (0, 0), and the gravity center positions of the two weighing tanks 5A, 6A are the support frame K (on the hopper flange 77). Correspondence) An example in which the coordinates are arranged at arbitrary two points is shown. Here, the two-dimensional center of gravity position coordinates of the center of gravity _{G 1} of the first measuring tank 5A _(x 1, _{y 1)} and then, the two-dimensional center of gravity position coordinates of the center of gravity _{G 2} of the second weighing vessel 6A _(x 2, y ₂ ). These barycentric position coordinates G ₁ : (x ₁ , y ₁ ) and G ₂ : (x ₂ , y ₂ ) are registered in advance in the storage unit 64 as the two-dimensional barycentric position information of the respective weighing tanks 5A and 6A. Further, the distance between the support points of the suspension support point by the first load cell 21A and the suspension support point by the second load cell 22A is S, and the suspension support point by the second load cell 22A (the suspension support point by the first load cell 21A) ) And the support point distance between the third load cell 23A and the suspension support point is R. The distances R and S between the support points are registered in advance in the storage unit 64 as basic information.

In FIG. 13, the load WA acting on the first load cell 21A, the load WB acting on the second load cell 22A, and the load WC acting on the third load cell 23A have the content weight of the first weighing tank 5A as w ₁ , If the content by weight of the weighing vessel 6A was w _2, represented by simultaneous equations of triplicate represented by the following formula (1) to (3).

WA = {w ₁ · (R−x ₁ ) (S−y ₁ )} / (R · S) +
{w ₂ · (R−x ₂ ) (S−y ₂ )} / (R · S) (1)

WB = {w ₁ · (R−x ₁ ) · y ₁ } / (R · S) +
{w ₂ · (R−x ₂ ) · y ₂ } / (R · S) (2)

WC = {w ₁ · x ₁ · y ₁ } / (R · S) +
{w ₂ · x ₂ · y ₂ } / (R · S) (3)

In addition, although these formulas (1) to (3) do not include the tare weight such as the weight of the support frame K supporting the weighing tanks 5A and 6A and the weight of the weighing tanks 5A and 6A themselves, this tare. Since the weight is a factor that does not change after the installation of the apparatus, the weight equation does not affect the simultaneous equations by resetting the load signals of the load cells 21A to 23A at the initial stage of the apparatus installation.

In the above formulas (1) to (3), R, S, x ₁ , x ₂ , y ₁ and y ₂ are known values, and w ₁ and w ₄ are the formulas (1) to (3). Can be obtained by solving two simultaneous equations composed of two equations arbitrarily selected from the above.

The weight calculation program created based on the measurement theory described above is stored in the storage unit 64 in advance, and when this weight calculation program is executed, the weight calculation unit 62 causes the A / D conversion unit 61 to generate a digital load signal. The load signals WA, WB, WC converted to, the center-of-gravity position coordinates G ₁ : (x ₁ , y ₁ ), G ₂ : (x ₂ , y ₂ ) stored in the storage unit 64, and between the support points Input the distances R, S, etc., perform the calculation to solve the two simultaneous equations consisting of two formulas arbitrarily selected from the formulas (1) to (3), and the contents of the measuring tanks 5A, 6A The weights w ₁ and w ₂ are calculated.

  Theoretically, in the example shown in FIG. 13, the number of weighing tanks is two, so the number of load cells required for weight calculation is two. However, since it is not stable to support the support frame K with only two load cells, the support frame K is supported with three load cells 21A to 23A.

According to a conveyor scale 1A of this modification, a load cell can be able to obtain the same advantageous effects as the conveyor scale 1 is of course depicted in Figure 1, is used in comparison with the conveyor scale 1 shown in FIG. 1 Can be significantly reduced.

By the way, if the support frames that support multiple weighing tanks are supported by at least the same number of load cells (load detectors) as the number of weighing tanks, the simultaneous equations necessary to determine the content weight of each weighing tank are established. In addition, the content weight of each weighing tank can be measured with the minimum necessary load cell. FIG. 14 and FIG. 14 show this as a representative example in which the support frame K that supports the four weighing tanks 91, 92, 93, 94 is suspended by the four load cells 101, 102, 103, 104. 15 will be described below as an embodiment of the present invention .

In FIG. 14, for convenience of explanation, the suspension support point by the first load cell 101 is the origin O: (0, 0), and the gravity center positions of the four weighing tanks 91 to 94 are arbitrary four points on the support frame K. An example of arrangement at the coordinates is shown. Here, the two-dimensional center-of-gravity position coordinates of the center of gravity G ₁ of the first weighing tank 91 are (x ₁ , y ₁ ), and the two-dimensional center-of-gravity position coordinates of the center of gravity G ₂ of the second weighing tank 92 are (x ₂ , y ₂ ), the two-dimensional center-of-gravity position coordinates of the center of gravity G ₃ of the third weighing tank 93 are (x ₃ , y ₃ ), and the two-dimensional center-of-gravity position coordinates of the center of gravity G ₄ of the fourth weighing tank 94 are (x ₄ , y ₄ ). These barycentric position coordinates G ₁ : (x ₁ , y ₁ ), G ₂ : (x ₂ , y ₂ ), G ₃ : (x ₃ , y ₃ ), G ₄ : (x ₄ , y ₄ ) are respectively It is registered in advance in the storage unit 64 as the two-dimensional center-of-gravity position information of the weighing tanks 91 to 94. Also, the distance between the support points of the suspension support point by the first load cell 101 and the suspension support point of the fourth load cell 104 and the support of the suspension support point by the second load cell 102 and the suspension support point by the third load cell 103 are supported. The distance between the points is R, and the distance between the support points of the first load cell 101 and the support points of the second load cell 102 and the support points of the third load cell 103 and the fourth load cell 104 are suspended. The distance between the support points with the lowered support point is assumed to be S. The distances R and S between the support points are registered in advance in the storage unit 64 as basic information.

In FIG. 14, a load WA acting on the first load cell 101, a load WB acting on the second load cell 102, a load WC acting on the third load cell 103, and a load WD acting on the fourth load cell 104 are represented by the first weighing tank 91. content weight of the w _1, the content by weight of the second weighing vessel 92 and w _2, if the content weight of the third measuring tank 93 and w _3, the content by weight of the fourth measuring tank 94 was set to w _4, the following It is represented by the four simultaneous equations shown by the equations (4) to (7).

WA = {w ₁ · (R−x ₁ ) (S−y ₁ )} / (R · S) +
{w ₂ · (R−x ₂ ) (S−y ₂ )} / (R · S) +
{w ₃ · (R−x ₃ ) (S−y ₃ )} / (R · S) +
{w ₄ · (R−x ₄ ) (S−y ₄ )} / (R · S) (4)

WB = {w ₁ · (R−x ₁ ) · y ₁ } / (R · S) +
{w ₂ · (R−x ₂ ) · y ₂ } / (R · S) +
{w ₃ · (R−x ₃ ) · y ₃ } / (R · S) +
{w ₄ · (R−x ₄ ) · y ₄ } / (R · S) (5)

WC = {w ₁ · x ₁ · y ₁ } / (R · S) +
{w ₂ · x ₂ · y ₂ } / (R · S) +
{w ₃ · x ₃ · y ₃ } / (R · S) +
{w ₄・ x ₄・ y ₄ } / (R ・ S) (6)

WD = {w ₁ · x ₁ · (S−y ₁ )} / (R · S) +
{w ₂ · x ₂ · (S−y ₂ )} / (R · S) +
{w ₃ · x ₃ · (S−y ₃ )} / (R · S) +
{w ₄ · x ₄ · (S−y ₄ )} / (R · S) (7)

In addition, although these formulas (4) to (7) do not include the tare weight such as the weight of the support frame K that supports the weighing tanks 91 to 94 and the weight of the weighing tanks 91 to 94 themselves, Since the weight is a factor that does not change after the installation of the apparatus, it becomes a weight item that does not affect the simultaneous equations by resetting the load signals of the load cells 101 to 104 at the initial stage of installation of the apparatus.

In the above formula _{(4) ~ (7),} R, S, x 1 ~x 4, y 1 ~y 4 is a known _value, so may be calculated to w 1 to w _4, the following equation which This is expressed by a determinant represented by (8).

とおくと、方程式の解ｗ_１〜ｗ_４はＡの逆行列を用いて以下の式（９）で示されるように一意的に求めることができる。

In the above formula (8),

In other words, the solutions w _{1 to} w ₄ of the equations can be uniquely obtained using the inverse matrix of A as shown in the following formula (9).

The weight calculation program created based on the measurement theory described above is stored in the storage unit 64 in advance, and when this weight calculation program is executed, the weight calculation unit 62 causes the A / D conversion unit 61 to generate a digital load signal. The load signals WA, WB, WC, and WD converted into, and barycentric position coordinates G ₁ : (x ₁ , y ₁ ), G ₂ : (x ₂ , y ₂ ), G stored in the storage unit 64 ₃ : (x ₃ , y ₃ ), G ₄ : (x ₄ , y ₄ ), the distances R and S between the support points, etc. are input, and the calculation based on the above equation (9) is performed to obtain each measuring tank 91. Content weights w ₁ , w ₂ , w ₃ , w ₄ of ˜94 are calculated.

  Therefore, even when the number of the plurality of weighing tanks mounted on the conveyor scale 1, 1 </ b> A is three or more, a support frame (for example, a hopper flange 77) that supports these weighing tanks is provided, and this support frame Is supported by at least the same number of load cells as the number of weighing tanks, and the content weight of each weighing tank is calculated based on the two-dimensional gravity center position information of each weighing tank and the load signal from each load cell. Therefore, weighing can be performed with the minimum necessary load cell, and the failure rate can be reduced, the device configuration can be made compact, and the cost can be reduced.

1 and FIG. 8, in the premise technique of the present invention, the transfer object input switching for switching the transfer of the transfer object from the upper belt conveyor 3 to the two weighing tanks 5 and 6 (5A, 6A). as a means, each measuring tank 5,6 (5A, 6A) by switching the damper position of the switching damper 42 is transferred object turned the switching device 7 configured to switch between the introduction of the transported object to is employed, the In the embodiment, a transported object input switching device 110 as shown in FIG. 16 is employed as a transported object input switching means when switching the input of the transported object from the upper belt conveyor 3 to the three weighing tanks. The

  16 (a) and 16 (b), the transferred object input switching device 110 is equally spaced on a partial circumference Q having a radius r with reference to a vertical line L passing through the downstream end point O of the upper belt conveyor 3. A chute 114 for guiding the object to be transported H that is dropped from the upper belt conveyor 3 with respect to each of the first measuring tank 111, the second measuring tank 112, and the third measuring tank 113 that are arranged with the tank centers aligned. It has. The chute 114 is swiveled along a partial circumference Q about a vertical line L by a swiveling mechanism 116 having a servo motor 115 as a drive source. A chute position command signal is output from the chute position switching control unit 117 to the servo motor 115, and a chute position signal indicating the current state position of the chute 114 is sent from the encoder 118 attached to the servo motor 115 to the chute position switching control unit. By feeding back to 117, the first chute position for guiding the conveyed object H from the upper belt conveyor 3 to the first weighing tank 111, and the conveyed object H from the upper belt conveyor 3 to the second weighing tank 112. The chute position switching control between the second chute position to be guided and the third chute position to guide the conveyed object H from the upper belt conveyor 3 to the third measuring tank 113 is performed.

Further, in the base technology of the present invention shown in FIGS. 1 and 8, the transported object discharging means for discharging the transported object put into the weighing tanks 5 and 6 (5A, 6A) onto the lower belt conveyor 3 is used. Gate opening / closing devices 31, 36, 80 configured to open / close the gates 17, 19 by operating the gate opening / closing operation air cylinders 34, 39 are employed. In the gate opening / closing devices 31, 36, and 80, it is difficult to adjust the discharge amount of the conveyed object, and thus the conveyed object may overflow from the lower belt conveyor 4. Therefore, by adopting the gate opening / closing device 120 shown in FIG. 17 in which the discharge amount of the conveyed object can be adjusted, such a problem can be surely prevented. In the following, the gate opening / closing device 120 applied to the first weighing tank 5 will be described, but the same applies to the gate opening / closing devices applied to the other weighing tanks 6, 5A, 6A, and the description thereof will be omitted. To do.

  In FIG. 17, the first gate 17 </ b> A is of a cut gate type that is rotatably attached to the first weighing hopper 16 via a pivot shaft 121. The gate opening / closing device 120 that opens and closes the first gate 17A includes a servo motor 122 that rotationally drives the first gate 17A. Then, a gate opening command signal is output from the gate opening / closing operation control unit 66A to the servo motor 122, and the current of the first gate 17A is transmitted from the encoder 123 attached to the servo motor 122 or the potentiometer 124 attached to the first gate 17A. A gate opening signal indicating the opening is fed back to the gate opening / closing operation control unit 66A, so that the opening of the first gate 17A can be changed steplessly.

  Here, the gate opening / closing operation control unit 66A monitors the content weight of the first weighing tank 5 calculated in real time by the weight calculation unit 62, and the first weighing hopper 16 is based on the degree of decrease in the content weight by this monitoring. The discharge flow rate of the object to be conveyed from is detected. Now, for example, when the opening degree of the first gate 17A is in a state as shown in FIG. 17C, when the gate opening / closing operation control unit 66A determines that the current discharge flow rate is large, the gate opening / closing operation control is performed. The unit 66A outputs a gate opening signal that decreases the opening of the first gate 17A to the servo motor 122. As a result, the opening of the first gate 17A is made smaller than the opening shown in FIG. 17C, and the opening shown in FIG. Material discharge flow is reduced. On the contrary, when the opening degree of the first gate 17A is in a state as shown in FIG. 17C, the gate opening / closing operation control unit 66A determines that the current discharge flow rate is small, The operation control unit 66A outputs a gate opening signal that increases the opening of the first gate 17A to the servo motor 122. As a result, the opening of the first gate 17A is made larger than the opening shown in FIG. 17C, and the opening shown in FIG. The discharge flow of objects is increased. In this way, since the discharge flow rate of the conveyed object is adjusted, the discharged amount of the conveyed object onto the lower belt conveyor 4 can be made appropriate.

The schematic block diagram of the conveyor scale used as the premise of this invention 1 is an enlarged view of the main part of FIG. FIG. 1 is a view taken along the line AA in FIG. FIG. 1 is a partially enlarged view of FIG. Schematic diagram of a control system of said conveyor scale Operation diagram of conveyor scale Flowchart explaining processing contents of control program Schematic configuration diagram of a conveyor scale according to the modification of FIG. Fig. 8 is an enlarged view of the main part. The figure which represents only the principal part by the BB arrow line view of FIG. FIG. 8 is a partially enlarged view of FIG. Schematic configuration diagram of a conveyor scale control system according to this modification Figure for explaining the measurement theory of the content weight of the measuring tank (1) The figure (2) for demonstrating the measurement theory of the content weight of a measurement tank in the conveyor scale which concerns on one Embodiment of this invention . FIG. (3) for explaining the measurement theory of the content weight of the measuring tank in the conveyor scale according to the embodiment of the present invention . Explanatory drawing of another example of a to-be-conveyed material input switching means Explanatory drawing of another example of a to-be-conveyed material discharge means Illustration of prior art

Explanation of symbols

1, 1A Conveyor Scale 3 Upper Belt Conveyor 4 Lower Belt Conveyor 5, 5A First Weighing Tank 6, 6A Second Weighing Tank 7 Conveyance Material Input Switching Device 31 First Gate Opening / Closing Device 36 Second Gate Opening / Closing Device 77 Hopper Flange 21 , 21A First load cell 22, 22A Second load cell 23, 23A Third load cell 24 Fourth load cell 25 Fifth load cell 26 Sixth load cell 62 Weight calculation unit 64 Storage unit

Claims (3)

It is a conveyor scale that weighs the object to be transported during transportation,
An upper belt conveyor disposed in the upper stage on the upstream side of the transport path;
A lower belt conveyor disposed in the lower stage on the downstream side of the conveying path;
Three or more measuring tanks placed in the middle of the conveyance path between the upper belt conveyor and the lower belt conveyor, into which the objects to be conveyed conveyed by the upper belt conveyor are put,
A support frame for supporting the three or more measuring tanks;
A to-be-conveyed material input switching damper for switching the input of the to-be-conveyed material from the upper belt conveyor to each weighing tank;
A weight measuring means for measuring the weight of the object to be conveyed put in each of the weighing tanks;
A transported object discharge gate for discharging the objects to be conveyed to the thrown into the measuring tank on the lower belt conveyor,
The weight measuring means includes at least the same number of load detectors as the number of the weighing tanks that support the support frame, a storage unit that stores the two-dimensional gravity center position information of each weighing tank, and the load detectors. A conveyor scale, comprising: a weight calculation unit that calculates a content weight of each weighing tank based on a load signal and barycentric position information stored in the storage unit . The weighing tank is composed of four weighing tanks of a first weighing tank, a second weighing tank, a third weighing tank, and a fourth weighing tank, and the load detector is a first load cell, a second load cell, a third weighing tank. It consists of four load cells, the load cell and the fourth load cell,
The suspension support point of the support frame by the first load cell is the origin O: (0, 0), and the gravity center positions of the four weighing tanks are arranged at arbitrary four points on the support frame,
The two-dimensional center-of-gravity position coordinates of the center of gravity of the first weighing tank are (x ₁ , y ₁ ), the two-dimensional center-of-gravity position coordinates of the center of gravity of the second weighing tank are (x ₂ , y ₂ ), and the third weighing The two-dimensional barycentric position coordinates of the center of gravity of the tank are (x ₃ , y ₃ ), the two-dimensional barycentric position coordinates of the center of gravity of the fourth weighing tank are (x ₄ , y ₄ ), and these barycentric position coordinates are measured. Register in advance in the storage unit as the two-dimensional center of gravity position information of the tank,
The distance between the support points of the suspension support point by the first load cell and the suspension support point of the fourth load cell and the distance between the support points of the suspension support point by the second load cell and the suspension support point by the third load cell Each distance is R, the distance between the support points of the suspension by the first load cell and the support point of the second load cell, and the support of the suspension by the third load cell and the fourth load cell. The distance between the support points with the point is set as S, and the distances between the support points R and S are registered in advance as basic information in the storage unit,
When the load acting on the first load cell is WA, the load acting on the second load cell is WB, the load acting on the third load cell is WC, and the load acting on the fourth load cell is WD, contents weight w ₁ of the measuring _tank, the contents weight w ₂ of the second measuring _tank, the contents weight w ₄ of the third contents by weight of the weighing vessel w ₃ and the fourth measuring tank 94, characterized in that obtained by the following equation The conveyor scale according to claim 1.

However,

The conveyor scale according to claim 1 or 2, wherein a discharge amount of the transferred object by the transferred object discharge gate is adjustable.

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